Web feeding and folding apparatus

ABSTRACT

Apparatus for feeding and folding an initially flat web to substantially U-shape by drawing the web down an inclined smooth surfaced plate that is decreasingly laterally tapered to terminate in a triangular forming region at its lower end wherein the moving web is gradually folded to U-shape and air under relatively low pressure is introduced between the moving web and the plate surface in the forming region.

United States Patent [191 Clancy WEB FEEDING AND FOLDING APPARATUS [75] Inventor: David Clancy, Canaan, Conn.

[73] Assignee: Colgate-Palmolive Company, New

York, NY.

[22] Filed: June 28, 1973 [21] Appl. No.: 374,625

[52] US. Cl 270/69; 270/86 [51] Int. Cl B65h 45/00 [58] Field of Search l. 270/69, 86, 94, 66

[56] References Cited UNITED STATES PATENTS 1,170,209 2/1916 Wood 270/86 Ramaika 270/86 June 17, 1975 Primary Examiner-Robert W. Michell Assistant ExaminerA. Heinz Attorney, Agent, or Firm-Strauch, Nolan, Neale, Nies & Kurz [57] ABSTRACT Apparatus for feeding and folding an initially flat web to substantially U-shape by drawing the web down an inclined smooth surfaced plate that is decreasingly laterally tapered to terminate in a triangular forming region at its lower end wherein the moving web is gradually folded to U-shape and air under relatively low pressure is introduced between the moving web and the plate surface in the forming region.

6 Claims, 5 Drawing Figures WEB FEEDING AND FOLDING APPARATUS This invention relates to web feeding and is particularly concerned with the feeding and folding of a laminated metal-plastic web in automatic packaging apparatus.

The invention will be described in its preferred embodiment as incorporated in a packaging apparatus of the type disclosed in US. Pat. No. 3,48 l .099 to David Clancy. As disclosed in that patent a laminated metalplastic web passes over a shaped smooth surfaced plow where it is laterally folded upon itself into a substantially V-shape preparatory to being longitudinally formed into upwardly open envelope compartments into which the material to be packaged is subsequently placed prior to final sealing. The present invention has for its major advantage novel apparatus that accomplishes the folding operation, and it will be understood that otherwise the apparatus may be that disclosed in the Clancy patent.

A highly advantageous feature of the invention is that the web is fed downwardly upon the smooth downwardly inclined decreasingly laterally tapered planar bottom surface of a forming member such as a rigid plate, with transverse folding starting gradually where the changing width of the plate surface becomes less than the width of the web and increasing as the folding web approaches the relatively sharp lower end of the plate, and during such folding a layer of air under pressure is introduced between the folding web and plate surface.

Further advantages and aspects of the invention will appear as the description proceeds in connection with the appended claims and the annexed drawings.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a relatively diagrammatic plan view illustrating apparatus of the invention according to a preferred embodiment;

FIG. 2 is a side elevation partly broken away and partly in section of the apparatus of FIG. 1;

FIG. 3 is a section showing the V-folded web substantially at the line 33 in FIG. 2;

FIG. 4 is an enlarged view in section showing a typical laminated web as at line 4-4 in FIG. 1; and

FIG. 5 is a fragmentary view partly in section showing a modification.

PREFERRED EMBODIMENTS A flat laminated web 11 passes from a supply roll in dicated at 12 over guide rolls 13 to the flat planar bottom surface 14 of an inclined rigid metal forming plate 15 that is suitably fixedly mounted by means (not shown) in the apparatus. In practice the plate 15 may be a solid aluminum plate of sufficient thickness to be rigid with its smooth bottom surface 14 inclined at an angle of about 30 to the horizontal. In this embodiment the web leaving the supply roll may be about six inches wide and, as illustrated in FIGS. 1 and 2, it first contacts the surface 14 at a region where that surface is wider than the web. FIG. 4 shows a typical web structure wherein a flexible aluminum foil F has a layer of thermoplastic material T on one surface and a layer of paper or plastic P on its other surface. The thennoplastic surface contacts surface 14 and is the inner surface of the folded web.

Preferably the web is centered with the longitudinal plate axis indicated at broken line 16 and as it descends the forming plate it reaches the laterally decreasingly tapered region 17 where, at the zone indicatedat broken line 18, the width of the web equals thewidth across the surface 14.

The plate region 19 extending downwardly from zone 18 is substantially triangular ending in a relatively sharp tip 21. As the web passes through the forming region 19 its central longitudinal area remains slidably engaged with surface 14 and its opposite lateral edges gradually move toward each other until they meet substantially in a plane indicated at 22 in FIG. 2 and as seen in FIG. 3. Movement of the web is effected by the intermittent feed roll pass 23 which may be the same as in said Clancy patent.

A fixed width compression throat 24 is provided to.

receive the folded web as it leaves the forming plate. In practice this throat maybe formed by two stationary posts 25 and 26 having laterally aligned parallel vertical corners or edges 27 and 28 sp'aced a predetermined distance apart, this distance being only slightly greater than the V-fold double thickness of the web.

Thus the web is gradually folded upon itself to the V- fold condition of FIG. 3 in passing over the forming region 19 of plate 15, and it is laterally compressed to 'retain that condition is passing through throat 24.

Some difficulty has been experienced in obtaining smooth feeding of the web through the forming region at 19, possibly due to electrostatic effects, particularly where the web may be of the structure shown in FIG. 4 and slides along the forming plate with its thermoplastic layer engaging surface 14. It has been found that this difficulty is eliminated by continuously introducing air under pressure into the space exaggeratedly shown at 29 in FIG. 2 between the surface 14 and the adjacent surface of the moving web in the folding region 19. This may be accomplished for example by providing a central opening 31 through the plate at region 19 and connecting thereto a conduit 32 from a suitable low pressure source of compressed air at P.

The degree of air pressure is not critical but it should not force the web appreciably away from surface 14. It has been found howeverthat when a pressure of a few pounds per square inch'is maintained here there seems to be established between the web and surface 14 a moving cushion layer of air occupying the space 29 that slightly displaces the central longitudinal area of the web from the forming surface, and in fact as the folded web passes the tip 21 the rounded lower end of the V- fold indicated at 33 in FIG. 3 and in FIG. 2 is located a small distance below the tip 21.

As a result of the foregoing it has been found that the combined folding and feeding of the web being drawn through the forming region are much more uniform and the web has less tendency to stick to the shaping surfaces. This improves the continuity and efficiency of operation of the entire packaging apparatus.

As shown in FIG. 5 the forming region 19 may comprise a triangular plate section separate from and detachably secured to the remainder of plate 15 as by screws 34.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by Letters Patent is:

1. In apparatus for feeding and folding a web of envelope forming material to an upwardly open substantially V-shape, an inclined metal forming plate having a flat, impervious, substantially triangular, planar, smooth bottom surface that is decreasingly laterally tapered toward its lower end, means for passing an initially flat web to and drawing it downwardly along said impervious surface, said impervious surface having a laterally extending zone wherein the width of the moving web becomes substantially equal to the width of said impervious surface and comprising the beginning of a forming region extending between that zone and the lower end of said impervious surface and wherein the moving web is gradually folded to said V-shape, said plate having a through opening that is substantially centrally located laterally in said forming region and a conduit connection from a source of air under pressure to said opening at the upper surface of said plate for introducing air under relatively low pressure between said web and said bottom surface in said forming region for facilitating movement of said web as it is drawn down said bottom surface, said plate further having a portion in said forming region detachably connected to said plate member and said portion having said through opening therein.

2. In the apparatus defined in claim 1 said plate comprising a rigid fixed triangular portion having a base wider than said web and an extended rectangular portion of the base width.

3. In the apparatus defined in' claim 1, said forming region terminating at its lower end in a relatively sharp tip.

4. In the apparatus defined in claim 3, means adjacent said tip defining a compression throat having a predetermined lateral width of about twice the thickness of said web.

5. In the apparatus defined in claim 4, said means for drawing the web downwardly along said surface comprising a vertical feed roll pass beyond said compression throat.

6. In the apparatus defined in claim 4, said compression throat means comprising a pair of fixed vertical parallel elements disposed to receive the folded web leaving said folding means. 

1. In apparatus for feeding and folding a web of envelope forming material to an upwardly open substantially V-shape, an inclined metal forming plate having a flat, impervious, substantially triangular, planar, smooth bottom surface that is decreasingly laterally tapered toward its lower End, means for passing an initially flat web to and drawing it downwardly along said impervious surface, said impervious surface having a laterally extending zone wherein the width of the moving web becomes substantially equal to the width of said impervious surface and comprising the beginning of a forming region extending between that zone and the lower end of said impervious surface and wherein the moving web is gradually folded to said Vshape, said plate having a through opening that is substantially centrally located laterally in said forming region and a conduit connection from a source of air under pressure to said opening at the upper surface of said plate for introducing air under relatively low pressure between said web and said bottom surface in said forming region for facilitating movement of said web as it is drawn down said bottom surface, said plate further having a portion in said forming region detachably connected to said plate member and said portion having said through opening therein.
 2. In the apparatus defined in claim 1 said plate comprising a rigid fixed triangular portion having a base wider than said web and an extended rectangular portion of the base width.
 3. In the apparatus defined in claim 1, said forming region terminating at its lower end in a relatively sharp tip.
 4. In the apparatus defined in claim 3, means adjacent said tip defining a compression throat having a predetermined lateral width of about twice the thickness of said web.
 5. In the apparatus defined in claim 4, said means for drawing the web downwardly along said surface comprising a vertical feed roll pass beyond said compression throat.
 6. In the apparatus defined in claim 4, said compression throat means comprising a pair of fixed vertical parallel elements disposed to receive the folded web leaving said folding means. 